Tungsten Carbide Blades put a quick sharp edge on dull or damaged knives. The carbide blades are reversible for extended life. 

Replacement Instructions

1. Remove the Phillips head screw(s) and save for re-assembly.
2. Remove the plastic cover and save for re-assembly.
3. Hold sharpender in hand with head facing down. Insert one of the carbide replacement blades into the left-hand cavity and then place the other blade into the right-hand cavity, which will be on top of the first blade. The blades should form a "V" in the middle. Both blades are designed to be interchangeable.
4. Replace the plastic cover.
5. Replace the Phillips head screw(s).